1. Field of the Invention
The present invention relates generally to imaging apparatuses. More particularly, the present invention relates to a technique suitable for shooting of moving images and still images.
2. Description of the Related Art
Video cameras for shooting images and recording the images on a recording medium, such as a memory card, are available. With a recent increase in the number of pixels of an image pickup element of the video cameras, shooting of high-definition still images as well as moving images has been realized. In addition, some video cameras can shoot still images during shooting of moving images. In such video cameras, still images can be shut in response to pressing of a shutter button during recording of moving images.
For example, a video camera disclosed in Japanese Patent Laid-Open No. 7-284058 encodes moving images according to the MPEG standard before recording the moving images. In response to a still image shooting instruction issued during recording of moving images, the video camera encodes a moving image as an intra-frame (I-frame). The video camera records the I-frame as still image data in a memory and then records the still image data on a recording medium after termination of shooting of the moving images.
In addition, a video camera disclosed in Japanese Patent Laid-Open No. 9-233410 has a buffer memory for still images. In response to a still image shooting request issued during recording of moving images, the video camera temporarily stores still image data in the buffer memory. After termination of recording of moving image data, the video camera reads out the still image data from the buffer memory and records the still image data on a recording medium.
An image recording apparatus disclosed in Japanese Patent Laid-Open No. 2005-12378 records moving image data on a first recording medium. In response to a still image shooting request issued during recording of moving image data, the image recording apparatus records the still image data on a second recording medium. After termination of recording of moving image data, the image recording apparatus copies the still image data recorded on the second recoding medium on the first recording medium.
However, the video camera disclosed in Japanese Patent Laid-Open No. 7-284058 records, as an I-frame, a frame corresponding to a timing of the still image shooting instruction issued during shooting of moving images. Accordingly, the image quality of reproduced moving image data undesirably decreases.
Additionally, the video camera disclosed in Japanese Patent Laid-Open No. 9-233410 records still image data in a buffer memory in response to a still image shooting instruction issued during shooting of moving images and then records the still image data on a recording medium after termination of shooting of moving images. If the video camera uses up an available buffer memory during shooting of moving images, the video camera can no longer shoot still images undesirably. In addition, since the video camera records still image data stored in the buffer on a recording medium after termination of shooting of moving images, a user may be unable to immediately perform a following operation, such as image shooting, until the video camera finishes recording the still image data on the recording medium.
Furthermore, the image recording apparatus disclosed in Japanese Patent Laid-Open No. 2005-12378 records still image data on another recording medium, which is different from a recording medium for storing moving image data, in response to a still image shooting instruction issued during shooting of moving images. After termination of shooting of moving images, the image recording apparatus records the still image data recorded on the other recording medium on the recording medium storing the moving image data. Accordingly, a user may be unable to immediately perform a following operation, such as image shooting, until the image recording apparatus finishes recording the still image data on the recording medium storing the moving image data after termination of shooting of moving images. In addition, the image recording apparatus has to be able to record moving images and still images on a plurality of recording media.
As described above, in the techniques disclosed in the above-cited documents, a still image is temporarily stored in a buffer memory in response to a still image shooting instruction issued during shooting of moving images. The still image is then recorded after termination of recording of moving images. Accordingly, if an available buffer memory for still images is used up during shooting of moving images, a restriction that no other still images can be shot and a restriction that a user cannot immediately perform a following operation after termination of recording of moving images are caused.
Thus, usability is unpreferable in the related art.